From f54d023836f03aa37c8b177f0c8c87463d7544a4 Mon Sep 17 00:00:00 2001
From: Phil Werli <phil.werli@teampicnic.com>
Date: Sun, 4 Dec 2022 11:59:50 +0100
Subject: [PATCH] Include a rule to rewrite `Mono.just(null)` to `Mono.empty()`

Should never happen in practice, but it's not a compile time error.
---
 .../tech/picnic/errorprone/refasterrules/ReactorRules.java    | 2 +-
 .../errorprone/refasterrules/ReactorRulesTestInput.java       | 4 ++--
 .../errorprone/refasterrules/ReactorRulesTestOutput.java      | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
index a614a88250..94d80a5c87 100644
--- a/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
+++ b/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/ReactorRules.java
@@ -64,7 +64,7 @@ Mono<T> after(Supplier<? extends T> supplier) {
   static final class MonoEmpty<T> {
     @BeforeTemplate
     Mono<T> before() {
-      return Mono.justOrEmpty(null);
+      return Refaster.anyOf(Mono.just(null), Mono.justOrEmpty(null));
     }
 
     @AfterTemplate
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
index d646c21ed0..e187eb487f 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestInput.java
@@ -34,8 +34,8 @@ ImmutableSet<Mono<?>> testMonoFromSupplier() {
         Mono.fromCallable(this::toString));
   }
 
-  Mono<String> testMonoEmpty() {
-    return Mono.justOrEmpty(null);
+  ImmutableSet<Mono<String>> testMonoEmpty() {
+    return ImmutableSet.of(Mono.just(null), Mono.justOrEmpty(null));
   }
 
   ImmutableSet<Mono<Integer>> testMonoJustOrEmpty() {
diff --git a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
index 50f7903137..c143647f84 100644
--- a/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
+++ b/error-prone-contrib/src/test/resources/tech/picnic/errorprone/refasterrules/ReactorRulesTestOutput.java
@@ -37,8 +37,8 @@ ImmutableSet<Mono<?>> testMonoFromSupplier() {
         Mono.fromSupplier(this::toString));
   }
 
-  Mono<String> testMonoEmpty() {
-    return Mono.empty();
+  ImmutableSet<Mono<String>> testMonoEmpty() {
+    return ImmutableSet.of(Mono.empty(), Mono.empty());
   }
 
   ImmutableSet<Mono<Integer>> testMonoJustOrEmpty() {